I downloaded the XF 1.4 Upgrade Package from the Customer Area, and attempt to Upgrade from XF 1.4 RC #2. So, i uploaded all Files and go to www.mypage.net/install - but there was this Error:
There are at least 2 file(s) that do not appear to have the expected contents. Reupload the XenForo files and refresh this page. Only continue if you are sure all files have been uploaded properly.